Process for producing substantially ash-free bituminous coal, subbituminous coal andlignite



W. J. BLOOMER Nov. 5, 1963 ETAL 3,109,803 LY ASH-FREE BITUMINOUS UMINoUsCOAL AND LIGNITE PROCESS FOR PRODUCI SUBSTANTIAL COAL, SUBBIT Filed Aug.5, 1959 INVE NTORS Bl. OMER WARD J. SAMUEL M M R TIN (0E CE A $50) BYBEVERLY 8. MART/N, ADMINISTRA TIP/X AGENTS* United States Patent O3,109,863 PRCESS FR PRUDUCHTQIG SUBSTANHALEJY ASH-FREE BiTUMENQUS CAL,SUBBHU- MENUS CAL ANB MGNHTE Ward J. lioomer, Westiield, NJ., and SamneiW. Martin, deceased, late of @air iarlr, ill., by Beverly B. Martin,administratrix, @fait Pari-r, lil., assignors to The Lummus Company, NewYork, NY., a corporation of Deiaware Fitted Aug. 3, 1959, Ser. No,331,312 6 Claims. (Cl. 20d-S) This invention relates to a process forproducing useful carbonaceous matter from coal and more particularlyrelates to a method of producing substantially ash-free coke from ade-ashed solution of carbonaceous matter prepared from a coal selectedfrom the group consisting of bituminous coal, subbituminous coal andlignite. This application relates to our co-pending applications SerialNos. 831,310 and 831,311, led on the even date herewith.

Presently, most calcined anode carbon is produced from petroleum coke,with the remainder being produced from the coke obtained by carbonizingcoal tar pitches. Considering the steadily increasing consumption ofpetroleum coke for manufacturing carbon anodes, coal represents a largepotential source of coke suitable for such purpose.

Coal is primarily comprised of three-dimensional, condensed, cyclicstructures of high molecular weight, such structures being predominantlysix-membered rings. Bituminous coal has been considered an intimatemixture of bitumen and humin which are similar in that both are large,flat aromatic lamellar structures, but differ in molecular size, degreeof aromaticity, oxygen content and the extent of cross linking.

Mineral matter, fusain and volatile matter and moisture primarilyconstitute the remaining components present in coal. Mineral matterdeposited in the sedimentary deposits by inliltration of ground watersduring coaliication and remaining after coal has been burned is calledash. Fusain, which is substantially consumed during the combustion ofcoal may be considered a mineral charcoal.

The rank of coal (i.e. the degree of coalification) is determined by itscarbon content which increases with the natural series of lignite,subbituminous coal and bituminous coal. In this series, the fixed carboncontent generally increases whereas the moisture and oxygen contentdecreases.

The presence of fusain, mineral matter (analyzed as ash) and combinedsulfur is the primary reason for the lack of utilization of coal forpreparing coke suitable for making anodes to be used in the productionof aluminum. Sulfur is usually present as organic sulfur, pyritic sulfurand/or inorganic sulfate. It is known that the ratio of inorganicsulfate and pyritic sulfur to organic sulfur increases with coals ofincreasing total sulfur content.

The following processes have been suggested for reducing fusain ormineral charcoal and minerai matter or ash present in various types ofcarbonaceous materials:

(l) Specific gravity separation or beneciation--a method of separatingthe materials having a low specific gravity from the heavier materialswhich contain a substantial portion of the ash and fusain.

(2) Flotation and electrostatic separation a process based on thedifferences between the surface properties of a coal particle and thatof an ash particle.

(3) Chemical extraction of the ash-a process wherein the ash present inthe raw coal is subjected to chemical attack, usually by an acid oralkali, to form soluble chemicals which are readily leached from thetreated coal.

(4) Solvent extraction-a process wherein the coal substance is dissolvedor extracted from the raw coal with a solvent to form a coal extractsolution. The insoluble ddd-ddd@ Patented Nov. 5, M1863 d components,viz., fusain or mineral charcoal, mineral matter or ash and some of theother impurities remain substantially unchanged and are consequentlysuspended in the solution. The components are thereafter separated fromthe solution by filtration, decantation or the like.

One solvent extraction or soivation process for preparing a coal extractpracticed in the past is referred to as the Pott-Broche process, namedafter Alfred Pott and Hans Broche. As described in their US. Patent No.1,881,927, a coal extract was prepared by treating one part of acarbonaceous material, such as pitcoal, lignite, peat and the like withtwo parts tetraline at a temperature of from 320 to 490 C. and at apressure of about 100 atmospheres to dissolve the coal substance. Theminimum temperature of extraction was determined by the decompositiontemperatures of the initial coal. The insoluble and undissolvedparticles were separated from the coal solution by centrifugation andthe tetraline was thereafter distilled from the solution to provide acoal extract which had a substantially smaller quantity of ash ascompared to the weight percent of ash originally present in the rawcarbonaceous material. The separation of the insoluble and undissolvedparticles from the solution was later found to be more effectivelyperformed by passing the coal solution through a multiplicity of ceramiclter candles. Solvent iosses occurring during the separation are one ofthe problems attending this technique of separation as well as othertechniques for separating mineral charcoal or fusain, and mineral matteror ash and like impurities from the solution. Another problem is thecoking of the various process lines during extraction and separation.

In U.S. Patent No. 2,166,321 Pott described a process for utilizing thecoal extract obtained by the aforementioned process to produce asemi-coke or full coke. The semi-coke or full coke was produced byblending the coal extract with a semi-coke (previously produced by theprocess) and charging the resultant mixture to a coke oven. The mixturewas heated in the coke oven to a temperature of from 450 to 1100 C. toproduce the semicoke or full coke depending on Whether a low or hightemperature, respectively, was maintained in the coking oven. The cokeproduct withdrawn from the coke oven had a low ash content and wassuitable for use as a metallurgical coke for manufacturing electrodes.

it is a principal object of our invention to provide a novel method forpreparing substantially ash-free coke from a coal selected from thegroup consisting of bituminous coal, subbituminous coal and lignite.

A further object of our invention is to provide a novel method forpreparing not only substantially ash-free coke but also valuableproducts, such as gas, aromatic solvents and oils, and ammonia from acoal selected from the group consisting of bituminous coal,subbituminous coal and lignite.

A still further object of our invention is to produce substantiallyash-free coke from a de-ashed coal solution prepared from a coalselected from the group consisting of bituminous coal, subbiturninouscoal and lignite.

Further objects and a fuller understanding of our invention may be hadby referring to the following description taken in conjunction with theaccompanying drawing, in which the figure is a schematic flow-diagramillustrating a preferred embodiment of the invention for producingsubstantially ash-free coke.

Prior to treatment in our novel process, the raw coal yto be treated iscrushed and ground in conventional crushing and grinding equipment. Theparticle size distribution may range up to l0 mm., however, we prefer aparticle size distribution whereby a major portion of `the coalparticles pass through a mesh screen.

ln Iaccordance with our invention 'we propose to digest and/ or dissolvethe extractable carbonaceous matter (which exclu-des fusain) present inthe pulverized raw coal under conditions of elevated temperatures andpressures utilizing a high boiling liquid solvent of high aromaticitythereby forming a solution of such extractable carbonaceous matter(hereinafter referred to as a coal solution). Fusain and the mineralmatter or ash are substantially unaffected by the solvent and aresuspended in the coal solution.

The coal solution while in a free flowing state is filtered to separatethe suspended insoluble solids (including undissolved extractablecarbonaceous matter) and is thereafter heated to a temperature aboveincipient coking `and passed to a coking unit. Product coke is withdrawnfrom the cok-ing unit and passed to subsequent processing unitsincluding coke handling and calcining facilities. The vaporous productsare withdrawn from the coking unit yand are introduced into afractionating unit wherein they are separated into various fractions,such as, for example: a light gas and gasoline fraction; a medium andheavy middle oil distillate fraction; and -a heavy bottoms distillatefraction. A portion or all of the high boiling liquid solvent of higharomaticity utilized for dissolving or digesting the extractablecarbonaceous matter present in the raw coal is derived from a distillatefraction recovered from the fractionating unit.

In preparing the coal solution, we prefer to use a ratio of high boilingliquid solvent to raw coal of from about 2:1 to about 3:1, however, aratio range of from 1/211 to 6:1 may be used. A lower ratio within therange of from zzl to about 11/2z1 does not as eliiciently dissolve ordigest the extractable carbonaceous matter whereas a higher ratio withinthe range of from yabout 3:1 to 6:1 places a heavier load on thefiltration unit and renders filtration uneconomical. Further, highsolvent ratios place an :additional heat load on subsequent heatingapparatus as a result of additional Vaporization requirements.

Solvation or digestion of the extractable carbonaceous matter isaccomplished in a solutizer or solvation vessel at throughput timesvarying vfrom about to 120 minutes. A temperature of from about 750 to825 F. and above the final decomposition temperature (where there issubstantial heat decomposition of the extractable carbonaceous matter)of the initial ycoal is preferably maintained in the solutizer. It isbelieved that within this temperature range, the cyclic,three-dimensional components of the coal are thermally depolymerizedwith the resulting constituents Ibeing soluble in the solvent. The coalsolution which is formed has physical properties similar to those of lowtemperature carbonization coal tar pitches. AOperating within thistemperature range, we have `dissolved more than 95% of the extractablecarbonaceous matter based on the available ash-free, fusainfree andsulfur-free coal. -Digestion or solvation may be performed attemperatures of from 600 to 850 F. however operating at the lowertemperatures within this range has the disadvantage of dissolving asubstantially .smaller portion of the extractable carbonaceous matterwhereas polymerization of the high boiling solvent and the coal solutionhas been observed at temperatures above about 825 F. `For effective andeiiicient solvation, polymerization of both the coal solution and thehighly aromatic solvent must be minimized. A pressure range of about 1to 7 or 8 atmospheres is preferably Ymaintained on the solutizer,however the solutizer may be operated at pressures up `to 100atmospheres. The preferred pressure range is substantially lower thanpressure ranges previously required, since the solvent has a higherboiling range as compared to the solvents, such as coal tar, water gastar, tetraline, phanthrene and anthracene oil which have been heretoforesuggested for solvation of theV extractable carbonaceous matter.

Filtration (including conventional `dewatering, washing and drying ofthe filter cake) of the coal solution is performed at a temperature offrom about 400` to 700 F.

i utilizing a metallic filter medium precoated |with a conventionalfilter aid. PrecoatingV the lter substantially improves the separationof undissolved and insoluble particles from the coal solution. With aprecoated filter, we have prepared filtered coal solutions which whenanalyzed for ash only varied between 0.08 to 0.02 weight percent,irrespective of the ash content of the raw coal which varied from 1 to20 percent.V This indicated that the efficiency of de-ashing byfiltration was a function of the size of the ash particle rather thanthe ash content. Using conventional diatornaceous earth filter aids, thecombustible carbonaceous matter of the filter cake is suliicient topermit its further use as fuel for process steam, and the like.Carbonaceous filter aids permit still Ifurther heat recovery from thefilter'cake.

The sulfur content of low sulfur coals (i.e. about 1.0 to 2.0 weightpercent sulfur) has been reduced to values of from 0.4 to 0.6% whichrepresented an average reduction of about 70 percent. Since the organicsulfur present in the raw coal is readily soluble in the highly aromaticsolvent, the quantity of sulfur separated from the raw coal is afunction of the pyritic and sulfate sulfur content of the `coal with thefinal sulfur content of the filtered coal solution primarily being afunction of .the organic sulfur content of the coal. With high sulfurcoals, the ratio of inorganic sulfate and pyritic sulfur to organicsulfur is normally greater than for low sulfur coals. Consequently, withhigh sulfur coals, we have observed a greater percentage-wise reductionof the sulfur content, reducing the sulfur content of the filtered coalsolution to as low as 0.6 weight percent, which corresponded to anover-all reduction of the sulfur content of from 70 to 90%.

The filtered coal solution is readily coked in any conventional cokingunit used for cokng petroleum feed stocks by heating the solution to a.temperature above its incipient coking temperature and thereafter cokingthe solution to produce substantially ash-free coke having a wide rangeof volatile matter, i.e. of about 4 to 26%.

We prefer to coke the coal solution in a delayed Acoking unit basicallycomprised of coke drums. Utilizing such a unit, the filtered coalsolution is heated to a temperature of from about 850 to 1050 F. and isintroduced into one of the coke drums. The lower limit above theincipient coking temperature to which the coal solution is heated isdictated by the upper limit of the volatile matter desired in the cokeproduct, normally about 8 to 16%. The upper limit above the incipientcoking temperature to which the coal solution is heated is dictated bythe lower limit of the volatile matter desired in the coke product,normally about 6 to 8%, since coke having less than 6% volatile matteris extremely hard and is consequently difficult toremove from the cokedrum.

The coal solution may also be coked in a contact coking unit (comprisedof a reactor having a downwardly flowing bed of a particulate materialon which the feed is spread and coked) and at higher temperatures so asto produce a coke having less than 6% volatile matter. Highertemperatures are permissible using a contact coking unit since there isnot the practical limitation of decoking a drum filled with coke of lessthan 6% volatile matter. Further, contact coking procedures do notVrequire preheating of the coker feed to a temperature above itsincipient coking temperature, since the feed may be heated in the colterto a temperature above incipient coking by the sensible heat of thecontact particles.

T he fractionating unit is controlled under conditions of temperatureand pressure to provide all or a portion of the highly aromatic liquidsolvent for the solvation of the coal. The initial boiling temperature(converted to one atmosphere) of such solvent is from 650 to 850 F. andhas physical properties similar to that of a low temperature tardistillate. It has been observed when processing bituminous coal thatsufficient solvent (for a 2:1 to 3:1 ratio of solvent to coal) isusually obtained from the fractionating unit by operating the unit toprovide a distillate having an initial boiling temperature (converted toone atmosphere) of about 750 F. The fractionating unit is preferablyoperated at from 1 to 7-8 atmospheres, however, it is generallycontemplated that pressures up to 100 atmospheres may be maintained onthe unit. The solutizer, may be considered to be an extension of thefractionating unit, but it is not necessary to operate both thefractionating unit and solutizer at the same pressure. Generally theoverall level of pressure in the solutizer will be at some higherpressure than the fractionating unit because of the normal increase ofsolutizer temperature over tower bottoms temperature and because of thepresence of some lower boiling coal decomposition products formed in thesolutizer. Solvent requirements may necessitate a higher pressure onboth units to provide more solvent from the fractionating unit by theinclusion of light ends normally lost to side streams and/or overheadwhen operating the fractionating unit at lower pressures.

Referring to the drawing, ground or pulverized coal selected from thegroup consisting of bituminous coal, subbituminous coal and lignite,and/or mixtures thereof are collected in a hopper 1 from which it isdistributed at a desired rate by a conveying mechanism 2 into asolutizer tank 3 maintained at a pressure of from about l to 7-8atmospheres. As illustrated, conveying mechanism 2 is a screw typefeeder which introduces the feed into solutizer 3 without loss ofpressure therein. Any conventional means of mechanical transfer maysuffice, providing the means allows for positive transfer of the coalinto solutizer 3 without a substantial loss of pressure therein.

The high boiling liquid solvent of high aromaticity is introduced intosolutizer 3 through line 4 at a rate so as to provide a ratio of solventto coal of from 1/2:1 to 6:1. Normally, we prefer a solvent to coalratio of from about 2:1 to about 3:1, since effective extraction ratesare obtained within this ratio range while minimizing filtration costs.Solutizer 3 is maintained at a temperature of from about 600 to 850 F.,preferably of from about 750 to 825 F. and above the final decompositiontemperature of the initial coal, whereby a substantial portion of theextractable carbonaceous matter in the raw coal is thermallydepolymerized. The products of depolymerization are soluble in thehighly aromatic solvent and thereby form, with the solvent, the coalsolution. Undissolved and insoluble solids including undissolvedextractable carbonaceous matter, and insoluble mineral matter or ash andmineral charcoal or fusain are suspended in the coal solution. Anagitator (not shown) may be provided to agitate the coal-solvent mixtureduring solvation.

Solvation temperatures are maintained in solutizer 3 by withdrawing andcirculating a portion of the coal solution and/ or coal-solvent mixturethrough an external heating system. The withdrawn portion is passedthrough line 5 by pump 6 under the control of valve 7 to heater 8 andthereafter reintroduced through line 9 into solutizer 3. In this manner,solvation temperatures are maintained within solutizer 3 without thenecessity of a high temperature and pressure heating system, which wouldbe the case, if the solvent was preheated to a temperature sufficient tomaintain solvation temperatures within the solutizer. A through-put timeof the raw coal of from 5 to 120 minutes is normally suicient todissolve or digest effectively and eiciently the extractablecarbonaceous matter. Since the solvent may have an initial boilingtemperature (converted to one atmosphere) as low as 650 F., whereassolvation temperatures may be as high as 850 F., solutizer 3 is providedwith vent line 10 under the control of valve 11 to permit the Withdrawalof the lower boiling components of the solvent and any volatile mattervaporized from the raw coal. In this respect, it has been observed thatthe quantity of volatile matter is practically negligible. Asubstantially uniform coal solution, wherein undissolved and insolublesolids are suspended, which include mineral charcoal or fusain andmineral matter or ash, is withdrawn through the bottom draw-off 12 andis drawn through cooler 13 by pump 14 and passed to a continuous rotaryfilter 15.

The coal solution is cooled to a temperature of from about 400 to 700 F.during its passage through cooler 13. Preferably, the rotary lter 15 isprecoated with conventional lter aids and is normally operated at apressure of about 40 to 60 p.s.i.g. to effect efficient removal ofsubstantially all of the suspended solids including undissolvedcarbonaceous matter. The filter cake is washed and dried to recoveradsorbed solvent and is withdrawn from filter 15 through line 16. Thesubstantially de-ashed coal solution is passed through line 17 to surgedrum 1S from which it is passed through line 19 and pump 20 to heater 21(a suitable coil heater). The coal solution is heated to a temperatureof from about 850 to 1050 F. in heater 21 and is passed therefromthrough line Z2 to a coking unit.

The coking unit, as illustrated, is a delayed coker and is comprised ofcoke drums 23 and 24. The heated coal solution in line 22 is introducedthrough line 22a into colter 23 wherein the charge is decomposed intocolte and a vaporous effluent. The coker overhead in. line 25a is passedthrough line 25 to a fractionating unit. While Coker 23 is being filledwith coke, coker 24 is being decolted with product colte withdrawnthrough lines 26a and 26 for subsequent processing. In normal operation,cooling and decoking of coker 24 is completed prior to the filling ofthe colrer 23. With the decoking completed on Coker 24 and having filledcoker 23 to a predetermined level, the coker charge is diverted tocolter 24 through line 22h, with the vaporous effluent in line 25b beingpassed to the fractionating unit through line 2S. After cooling, coker23 is decoked with product coke being passed through lines 26b and 26for subsequent processing.

rIhe coker overhead in line 25 is introduced into a fractionating orcombination tower 27 which is provided with suitable fractionating decks(not shown). Introduction of the etiiuent into the tower may result insome foaming. This may be effectively inhibited by the addition of asmall amount of an anti-foam agent, at the point of introduction or atsome elevated point in the tower. The hereinbefore mentioned distillateand volatile matter in line 10, which are evolved during solvation, areintroduced into the lower portion of the tower 27.

The combination tower overhead products in line y23 comprisingcondensible and non-condensible components are passed to conventionalprocessing units to separate the condon-sible components from thenon-condensible components. A medium and heavy middle oil is Withdrawnfrom an intermediate point on the tower 27 through line 29 by pump 30and is passed .through line 31 to refining units (not shown). A portionof the middle oil in line 29, under the control of valve 32, is passedthrough line 35, waste heat boiler 34, and line 35 and is thereaftersplit into at least two portions (lin-es 35a and 3515) for introductionas reflux into tower 27.

Tower bottoms in line 36 are passed to surge tank 37. By properlycontrolling the temperature level within tower 27, the distillatefraction in line 36 has an ititial boiling temperature (converted to oneatmosphere) of from 650 to 850 F. and represents all or a portion of thesolvent to be used for dissolving or digesting the extractablecarbonaceous matter in the pulverized raw coal feed. As hereinbeforementioned, when processing bituminous coal, solvent requirements mayusually be satisfied by operating the -fractionating unit so as toobtain a distillate having an initial boiling temperature (converted toone atmosphere) of about 750 1F. If additional solvent is required (overthe 750 F. distillate) the fractionating unit may be operated to providea distillate having an initial boiling temperature (converted to oneatmosphere) as low as 650 F. or desired, the fractionating unit may beoperated to provide the latter distillate, withdrawing excess solventover -solutizer requirements for utilization in other processes.

. 37 is superfluous.

Start-up or malte-up solvent is introduced into sunge tank 37 throughline 38 under the control of valve 39. The quantity of solvent necessaryto provide .a solvent to coal ratio of from 1/2 :1 to 6:1 is Withdrawnfrom tank 37 through line 40 and passed by pump 41 under the con- 5 trolof valve 42 into line 4. After start-up, should the quantity of captivesolvent exceed solvation requirements, excess solvent may be withdrawnfrom tank 37 through line 43 under the control of valve 4.4. It isgenerally contemplated that solvent requirements for the solvation ofbituminous coal maybe fulfilled by controlling the operating temperatureand pressure of the combination tower so as to permit the'directintroduction of the distillate fraction inline 36 to solutizer 3, inwhich case, surge tank The following examples will further illustratethe nature o-f this invention, it being understood that the invention isnot limited to the operating conditions or quantities therein:

Example l In accordance with our invention a bituminous coal having thefollowing proximate analysis:

were introduced into the solutizer zone to provide a 3 to 1 ratio ofsolvent to coal. The mixture was agitated while maintaining atemperature of 800 F. and a pressure of 5 atmospheres. The resultingcoal solution was cooled to a temperature of 450 and passed through afilter precoated with a standard lter aid. The filtered coal solutionrepresented an 86.3% recovery of extractable carbonaceous matter basedon the crushed coal and had the following properties:

Properties: 45 Sp. gravity (100/100 iF.) 1.2407 Softening point, F.(B+R) 152 Sulfur (wt. percent) 0.46 Carbon residue (wt. percent)-Ramsbottom 30.9

Conradson 3 1.3 CS2 solubility (-wt. percent)- Bitumen 76.66

Ash 0.02

Difference 23,22

The filtered coal solution was heated to 910 F. and coked to provide acoke which was recovered from the coker having the following properties:

Properties: Wt. percent Volatile matter 10.9 Sulfur 0.27 Ash 0.13 Iron0.036 Silicon 0.009 R203 0.112 Nickel 0.0073 Titanium 0.013 Vanadium0.00024 Boron, p.p.rn.

Example Il Following the procedures of Example I, a bituminous coalhaving identical properties as the coal in Example I and a distillatehaving an initial boiling temperature (converted to one atmosphere) ofabout 750 F. were introduced into the solutizer zone to provide a 2 to 1ratio of solvent to coal. The mixture was agitated while maintaining apressure of 5 atmospheres and a temperature of 800 F. The resulting coalsolution was cooled to a temperature of about 450 IF. and passed througha filter precoated with a standard iter aid. The iiltered coal solutionrepresented a 67.5% recovery of extractable carbonaceous matter based onwhole coal and had the fol- The filtered coal solution was heated to 910F. and coked to provide a coke which was removed from the Coker havingthe following properties:

Properties:

Volatile matter wt. percent-- V6.5 Sulfur do 0.28 Ash do 0.12 iron do0.025 Silicon do 0.003 R203 do 0.096 Nickel do 0.0015 Titanium 'do 0.014Vanad-um do 0.00024 Boron p.p.m 10

rl`he quality of the coke prepared according to the above examples matchthat of coke prepared from the best petroleum residue.

The overhead from the coker was condensed and had the Ifolio-wingproperties:

Properties:

Specific Gravity- -At 10G/60 F. 1.148

At 25/25 C. 1.160 Viscosity at 210 F., centipoises 12.0 Conradson carbon(wt. percent) 0.18 Sulfonation residue None lSulfur (wt. percent) 0.38

Of the coker effluent, about 50% had an initial boiling temperatureabove 750 F.

While We have shown and'described a preferred form of oui invention, weare aware that variations may be made thereto and we, therefore desire abroad interpretation of our invention within the scope of the disclosureherein 'and the following claims.

We claim:

1. A method of producing substantially ash-free coke and valuableconstituents from a de-ashed solution of carbonaceous -matter preparedfrom a coal selected from the group consisting of bituminous coal,subfbitum-inous coal and lignite in a high lboiling point hydrocarbonsolvent of high aromaticity having an initialboiling temperature ofabove about 750 F. from which solution substantially all suspendedmineral matter, fusain and sulfur has been removed which comprises:heating of all said solution to a temperature of from about 850 to 1050F.; introducing said heated solution in liquid stream into a reactionZone wherein all of said solution is thermally decomposed into vapor andash-free, fusainfree and sulfur-free coke; withdrawing as product fromsaid reaction zone said substantially ash-free coke; withdrawing saidvapor from said reaction zone and introducing said vapors into afractionating zone; and fractionating said vapors to obtain a heavydistillate fraction having 9 an initial boiling temperature (convertedto one atmosphere) from 650 to 850 F.

2. A method of producinfy substantially ash-free coke and -a valuableconstituent from a defashed'solution of carbonaceous matter preparedfrom a coal selected from the group consisting of bituminous coal,sub-bituminous coal and lignite in a high boiling point hydrocarbonsolvent o-f high `aromatici-ty having an initial boiling temperature ofabove about 750 F. from which solution substantially Vall suspendedmineral matter, fusain and sulfur has been removed Iwhich comprises:heating of all said solution to a temperature above its incipient cokingtempera-ture; introducing said heated solution in liquid stream into areaction zone wherein ail of said solution is the mally decomposed intovapors and substantially ashfree, fusain-free and sulfur-free coke;withdrawing as product from said reaction zone said substantiallyashfree, fusain-free and sulfur-free coke; withdrawing said vapors fromsaid reaction zone and introducing said vapors into a fractionatingzone, and fractionating said vapors to obtain a heavy distillatefraction, having an initial boiling temperature (converted to oneatmosphere) of from 650 to 850 F.

3. A method of producing substantially ash-free coke and valuableconstituents from a de-asfhed solution of carbonaceous matter preparedfrom a coal selected from the group consisting of bituminous coal,sub-bituminous coal land lignite in a high boiling point hydrocarbonsolvent of high aromaticity having an initial boiling temperature ofabove about 750 F. from which-solution substantially all suspendedmineral matter, fusain and sulfur has been removed which comprises:heating of said solution to a temperature of from about 850 to l050= F.;introducing of all said heated solution in :liquid stream into areaction zone wherein all of said solution is thermally decomposed intovapors and substantially ash-free, fusain-free and sulfur-free coke;withdrawing as product from said reaction zone said substantiallyash-free, fusainfree yand sulfur-free coke; land withdrawing saidfollowing constituents from said reaction Zone said vapors.

4. A method of producing substantially ash-free colte and a valuableconstituent lfrom a de-ashed solution of carbonaceous mratter preparedfrom a coal selected from the group consisting of bituminous coal,sub-bituminous coa-l and lignite in a high boiling point hydrocarbonsolvent of high aromaticity having an initial boiling temperature ofabove about 750 F. from which solution substantially kall suspendedmineral matter, fusain and sulfur has been removed which comprises:heating of all said solution to a temperature above its incipient cokingtemperature; introducing; of all said heated solution in liquid streaminto reaction zone wherein all of said solution is thermally decomposedinto vapors and substantially ash-hee, fusain-free and sulfur-freecolte; withdrawing as 10 product from said reaction zone saidsubstantially ashfree, fusain-free and sulfur-free coke; and withdrawingas said valuable constituents from said reaction zone said vapors.

5. A method of producing substantially ash-free colte and valuableconstituents trom a de-ashed solution ot carbonaceous matter prepared`from a coal selected from the group consisting of bituminous coal,sub-,bituminous coal `and lignite in a high boiling point hydrocarbonsolvent of high Varomaticity having an initial boiling temperature ofabove about 750 F. from lwhich solution substantially all suspendedmineral matter, fusain land sulfur has been removed which comprises:heating of `all said solution to a temperature of from about 850 to10.50 F.; introducing all of said heated solution in liquid stream intoa reaction zone wherein said `solution is thermally decomposed intovapors and substantially `ash-free, fusain- Ifree and sulfur-free coke;withdrawing as product from said reaction zone said substantiallyash-free, fusain-free `and sulfur-)Grec coke; withdrawing said vaporslfrom said reaction zone and introducing said vapors into 'afractionating zone; and fractionating said vapors to obtain a heavydistillate fraction having :an initial. boiling temperature (convertedto one atmosphere) above about 750 F.

6. A method of producing substantially ash-free coke and a valuableconstituent from a de-ashed solution of carbonaceous matter preparedfrom `a coal selected yfrom the group consisting of bituminous coal,sub-bituminous coal and lignite in a high boiling point hydrocarbonsoflvent of high aromatioity having an initial boiling ternperature ofabove about 750 F. from which solution substantially all suspendedmineral matter, fusain and sulfur has been removed which comprises:heating of all said solution to a temperature above its incipient cokingtemperature; introducing of all said 'heated solution in liquid streaminto a reaction zone wherein all or" said soiution is thermallydecomposed into vapors and substantially ash-free, fusain-free yandsulfur-free coke; withdrawing as product from said reaction zone saidsubstantially ashfree, fusain-free and sulfur-free coke; withdrawingsaid vapors from said reaction and introducing said vapors into afractionating zone; and fractionating said vapors to obtain a heavydistillate `fraction having an initial boiling `temperature (convertedto one atmosphere) above about 750 F.

References Cited in the file of this patent UNITED STATES PATENTS1,881,927 Pott et al Oct. l1, 1932 2,215,869 Buetesch et al. Sept. 24,1940 2,221,410 Pier 1 Nov. 12, 1940 2,664,390 Pevere et al Dec. 29, 19532,714,086 Bluemner July 26, 1955 .Patent No. 3,109,803

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION November 5, 1963Ward J. Bloomer et al.

ppears in the above numbered pat- It is hereby certified that error a idLetters Patent should read as ent requiring correction and that the saCorrected below.

In the sheet of drawing and in the heading to the printed specification, title of invention, for "PROCESS FOR PRODUCING SUBSTANTIALLYASH-FREE BITUMINOUS COAL, SUBBUTUMINOUS COAL AND LIGNITE", eachoccurrence, read PROCESS FOR PRODUCING SUBSTANTIALLY ASH-FREE COKE FROVIBITUMINOUS COAL, SUBBITUMINOUS COAL AND LIGNITE Signed and sealed this18th day of August 1964.

(SEAL) mest:

EDWARD J. BRENNER :.:RNEST W. SWIDER Commissioner of Patents nestingOfficer

1. A METHOD OF PRODUCING SUBSTANTIALLY ASH-FREE COKE AND VALUABLECONSTITUENTS FROM A DE-ASHED SOLUTION OF CARBONACEOUS MATTER PREPAREDFROM A COAL SELECTED FROM THE GROUP CONSISTING OF BITUMINOUS COAL,SUB-BITUMINOUS COAL AND LIGNITE IN A HIGH BOILING POINT HYDROCARBONSOLVENT OF HIGH AROMATICITY HAVING AN INITIAL BOILING TEMPERATURE OFABOVE ABOUT 750*F. FROM WHICH SOLUTION SUBSTANTIALLY ALL SUSPENDEDMINERAL MATTER, FUSAIN AND SULFUR HAS BEEN REMOVED WHICH COMPRISES:HEATING OF ALL SAID SOLUTION TO A TEMPERATURE OF FROM ABOUT 850* TO1050*F.; INTRODUCING SAID HEATED SOLUTION IN LIQUID STREAM INTO AREACTION ZONE WHEREIN ALL OF SAID SOLUTION IS THERMALLY DECOMPOSED INTOVAPOR AND ASH-FREE, FUSAINFREE AND SULFUR-FREE COKE; WITHDRAWING ASPRODUCT FROM SAID REACTION ZONE SAID SUBSTANTIALLY ASH-FREE COKE;WITHDRAWING SAID VAPOR FROM SAID REACTION ZONE AND INTRODUCING SAIDVAPORS INTO A FRACTIONATING ZONE; AND FRACTIONATING SAID VAPORS TOOBTAIN A HEAVY DISTILLATE FRACTION HAVING